Adjustable mobile scaffold



Nov. 26,` 1963 Filed Marchi' 1,

J. F. LANGER ADJUSTABLE MOBILE scm-OLD 5 sheets-sheet 1 +R MM Jo/4v F LA NGE/Q T' TOP/VL' YS Nov. 26, 1963 J. F. LANGER 3,112,009

ADJUSTABLE MOBILE SCAFFOLD Filed March 1, 1963 5 Sheets-Sheet 2 I, U 40 l 47 47a. '[136 /5 Il. M y 34 4 JZ. j 45K/ 3 f6 FLNVENTOR i JOHN A/vGE/l?` F1618 BY wwf/M ATTORNEYS Nov. 26, 1963 J, F, LANGER 3,112,009

ADJUSTABLE MOBILE SCAFFOLD Filed March 1, 1965 5 Sheets-Sheet 5 INVENTOR.

JOHN E LANGE/f? ATTORNEYS NOV. 26, 1963 J, F, LANGER I 3,112,009

ADJUSTABLE MOBILE SCAFFOLD Filed March l, 1963 5 Sheets-Sheet 4 IN VEN TOR JOHN F LANGER fzc. 3l l y WW/WMA AT TQENEKS Nov. 26, 1963 J. F. LANGER 3,112,009

I ADJUSTABLE MOBILE SCAFFOLD Filed March 1, 1963 5 Sheets-Sheet 5 FIG. .IZ /77 7a i l INVENTOR JOHN F LANGER Av- 'ron/vans United States Patent O 3,112,009 ADJUSTABLE MOBlLE SCAFFQLD John F. Langer, 903 1st Ave., Faribault, Minn. Filed Mar. l, 1963, Ser. No. 262,023 6 Claims. (Cl. 182-14) My invention relates generally to scaffolding and more particularly to improvements in prefabricated rela-tively permanent scaffolding of the mobile type.

Still more specifically, my invention relates to and pnoyides a novel adjustable self-propelled scaffold and has @or its primary object, the provision of such a structure which may be readily transported and quickly and safely anchored.

A further object of my invention is the provision of a device of the class above-described which is provided with means for selectively raising and lowering an occupant to different working levels.

A still further and highly important object of my invention is the provision of a device which is rugged in construction, durable in use, and which may be manipulated with a minimum of skill and effort.

The above and still other important objects tof my invention will become apparent from the following detailed specification, appended claims and attached drawings.

Referring to the drawings wherein like characters indicate like parts throughout the `several views:

FIG. Il is a View in side elevation of my novel structure;

FIG. 2. is a view in front elevation;

FIG. 3 is a View in top plan, some par-ts thereof being broken away;

FIG. 4 is a fragmentary sectional View taken substantially on the line -e-i of FIG. 2;

FIG. 5 is a View in section as seen from the line 5-5 of FIG. 4;

FIG. 6 is an enlarged sectional View taken on the line 6 6 of FIG. `l;

FIG. 7 is an enlarged detailed view in elevation of a portion of the structure shown in FIG. 2;

FIG. 8 is a View in elevation as seen from left to right of FIG. 7;

FIG. 9 is an enlarged view in section as seen from the line 9-9 of FIG. l;

FIG. l() is a View in section as seen substantially from the line lil-1G of FIG. 9, some parts thereof being shown in elevation and some parts being broken away and shown in section;

FIG. ll is an enlarged lfragmentary view as seen from the line 11-11 of FIG. 2, portions thereof being broken away and shown in section;

FIG. 12 is an enlarged view in horizontal section as seen from the line 12-12 of FIG. 2; and

FIG. 1-3 is a sectional View as seen from the line ifil of FIG. 12.

Referring with greater particularity to the drawings, the numeral 1 indicates in its entirety a mobile frame comprising an elongated generally rectangular main frame section 2 and a detachable extension section 3. The frame sections 2, 3 may be formed from suitable channel iron or the like and may have any suitable means for detachably securing same together, such as by cooperating nutequipped plates generally identified by 4. Preferably, and as shown, the frame extension section 3 is generally triangular in shape and projects laterally from the outer side frame member 2a of the main frame section 2. and is provided at its apex with an `Outrigger wheel 5 which, for purposes hereinafter to be explained in detail, is made vertically adjustable through the medium of a screw jack 6. The inside frame member of the main frame 2 is identified by 2b, and the cross frame members connecting opposite ends by 2c and 2d.

imparting mobility to the main frame 2- are wheel means di lg@ Patented Nov. 26, 1963 adjacent opposite ends identified respectively as 7 and S. Wheel means 7', shown as comprising a pair of laterally spaced wheels 7u, impart steering movements to the main frame 2.. `Wheels 7a, as shown, are mounted on a spindle 9 journalled in a vertical bearing lll fast on the frame 2. Fast on the upper end of the spindle 9, shown particularly in FIG. 4, is a generally horizontally disposed crankarm lll which, at its outer end, is pivotally connected as at l2, to one end of a link 13. The opposite end of the link 13 is connected at le to the intermediate portion of an opstanding lever l5, the lower end of which is pivotally ecured as at lo, to a suitable mounting plate or bracket 17 carried by lthe frame 2, see particularly FIG. 2. For the purpose of locking i he lever l5 and cooperating steering parts carried thereby in a desired set position, a customary segmental ratchet lli and cooperating spring-biased locking rod 19 is provided. As shown particularly in FIG. 5, the yielding means -is in the nature of a coiled coinpression spring Ztl encompasing the locking rod i9, and interposed between the stop member 2l carried by the lever le' and a further stop 22 fast on the rod lig.

The wheel 8 is suitably journalled between a pair of bearing equipped mounting plates 213 on an axle 2d to which it is made fast. Also fast fon the axle 24 is a sprocket 25 having entrained thereover a link chain or the like 26. Link chain :26 is likewise entrained over a drive pulley 27 fast on a driven shaft 28 -on a gear reduction unit 21g. Rotary movement is imparted to the gear reduction unit 29' through the medium of an electric motor vor the like 3i) having a V-belt or other flexible connection 3l running over its drive sheave 32 and over a larger sheave 33 on the input end of the reduction unit 29.

The generally rectangular area defined by the main frame 2 is identied by the letter A. Overlying the greater part of this area A and above the level of the wheels 7, 8, is a primary platform 34 which may be formed from any rigid material such as steel plate. Rigidly anchored to and upstanding from the primary platform 34. is suitable `superstructure identified in its entirety by 35 and including a guard rail forming portion 3o and an upper ladder forming portion G7. Both of said lower and upper portions 36, 37 cooperate to define steps or rungs 38. As shown particularly in FIG. 2, the upper superstructure 37 is laterally offset intermediate its upper and lower ends, as at 39, for a purpose which will hereinafter be explained in detail and is thus provided with an offset secondary platform lill.. At its lower end, the upper superstructure portion 37 is pivotally connected on a vertical axis to the lower section 36 through the medium of a spindle all rigidly mounted ion and carried by the lower section 3o, and a bearing equipped block f-Z- held fast within a rectangular mounting frame 43 which is, in turn, rigidly secured to the lower end portions of vthe vertically disposed tubular elements 44 making up the upper superstructure portion 37. As shown particularly in FIG.. l0, the mounting block 42. is ro-tatively received on the spindle 4l.

ylt should be here noted that the upper tubular portion 37 may be manually rotated about the axis of the spindle 4l whereby to project the offset portion 39 and platform 4@ carried thereby laterally irom the inner side frame member 2b, to bring a worker closer vto the side of a building or other object being worked upon, see particularly FIG. 2, or alternatively, to move same within the limits of the frame member 2 for purposes of transportation or storage. More accurate adjustments in this regard, as may be necessitated by the terrain, may be brought about by impar-ting raising and lowering movements to the Outrigger wheel S.

To positively lock the upper superstructure portion 37 for rotation about the axis of spindle ril, the mounting frame i3 is provided with a vertically raisable and lowerable locking dog i5 which is selectively receivable in circumferentially spaced apertures 46 on the upper end of lower portion 36 of the superstructure and which are alignable with the locking dog 45 upon rotation of the mounting frame 43.

Mounting and guiding the primary platform 34, together with the superstructure for vertical raising and lowering movements are upstanding parallel guide rails 47, one each of which is carried by one of the end frame members 2c and 2d. As shown, these guide rails 47 are in the form of T-members, the opposite side edges 47a of which form rails for the reception of grooved roller elements 4S journalled for rotation on plates 49 fast on the mounting brackets 59 secured to opposite ends of the primary platform 34.

For the purpose of imparting raising and lowering movements to the primary platform 34 and parts carried thereby upon the guide rails 47, I provide an electric motor 51 suitably supported by the frame member l below the level of the primary platform 34. Entrained over the drive pulley 52 of the motor 51 and a greatly enlarged pulley 53 associated with the reduction gear 54 is a V-belt or the like 5S. Entrained over a drive sprocket 56 associated with the gear reduction unit 54 and over a sprocket 57 associated with a braking mechanism 58 is a link chain or the like 59. Brake 58 is of the conventional band type and is, as shown particularly in FIG. 5, provided with an operating solenoid 6i). As shown, the sprocket S7 is fast on one end of a shaft 6l, to the opposite end of which is made fast a sprocket 62. Entrained over sprocket 62 and over a large sprocket 63 on a rotary shaft 64 is another link chain 65. As shown, the shaft 64 extends longitudinally of the main frame 2, in closely spaced parallel relation to the outer frame member 2a, and is journalled in longitudinally spaced bearings 66 carried by the frame 2. Adjacent its opposite ends the shaft 64 is provided with winding spools 67. A pair of exible cables 68 each have one of their ends fast on the shaft 64 for winding engagement by one of the winding spools 67. From their respective winding spools 67 the cables 68 extend one each over a pulley 69 suitably bracketed on the upper end portion of one each of the guide rails 47; and the opposite ends of said cables 63 are made fast on the plates 49 carried by the platform 34.

To impart stability to the platform during raising and lowering movements on the guide rails 47, and particularly to increase the tension of the rollers 48 on which rails 47a I provide a spring-equipped take-up mechanism identified in its entirety by 70. inasmuch as this device forms no part of the instant invention, it is not felt necessary to describe same in further detail.

For the purpose of imparting movements to the electric motors 30, 51 (both of which are of the reversible type) and in controlling said movements, I provide independent control switches 71 and 72, respectively which, for purposes of convenience, are contained in a common housing 73. Preferably, and as shown, the housing 73 is provided at its rear with downwardly opening hook elements 74 which are adapted to supportingly receive any horizontally disposed portion of the superstructure 35. In this manner, as indicated by full and dotted lines in FIG. l, the control switches 71 and 72 may be readily accessible by an operator standing either on the primary platform 34 or on the secondary platform 4f).

With respect to the brake 58, it might here be stated that same frictionally holds the platform 34 and superstructure 35 carried thereby in any desired elevated position, the braking action thereof being interrupted only by energization of the solenoid 6i) when the circuit is closed by manipulation of the switch 72. The circuitry between the motors 30, 51 and parts associated therewith is entirely conventional and, consequently, it is not felt that a wiring diagram is necessary. It suffices to state that the electrical conduit 76 leading from the switches 71, 72 has its intermediate portion so supported L by one of the guide rails 47 in a manner to permit raising and lowering of the superstructure 35, irrespective of the position of the housing 73.

So as to enable my novel portable scaffold to be stored or shipped in a minimum of space, it is obvious that the superstructure 35, the guide rails 47 and the frame 1, may be formed to provide detachable sections. In line with this I have shown the upper portion 37 of the superstructure 35 as being formed to provide telescoping joints as indicated at 37a, see particularly FIG. l1. When the extension frame section 3 is detached from the main frame section 2, for purposes either of storage or running same through a restricted opening, the Outrigger wheel 5 may be detached from the extension section 3 and attached to the side frame member 2a, as indicated by dotted lines in FIG. 3. Finally, for the purpose of imparting lateral stability to the frame 1, particularly when the upper platform 40 is in the laterally offset position of FiG. 2, I provide a counterweight 77 which is retained in its laterally extended position by means of a supporting plate 78 carried by the apex 79 of the triangular extension frame 3 and tie bar S9 interposed between and attached to side rails 2a, 2b, and plate 78 by any suitable means, such as bolts 81, to prevent withdrawal of the tie bar 80 from the frame members 2a, 2b when it is desired to separate the frame sections 2, 3.

My invention has been thoroughly tested and found to be completely satisfactory for the accomplishment of the above objects, and while I have shown a preferred embodiment thereof, I wish it to be understood that same may be capable of modification without departure from the scope and spirit of the appended claims.

What is claimed is:

l. In a device of the class described,

( a) a mobile frame,

(b) a primary platform overlying in part said frame, and mounted and guided thereon for raising and lowering movements relative thereto,

(c) power means for imparting said raising and lowering movements to said primary platform,

(d) power means for imparting forward and rearward movements to said mobile frame,

(e) independent control means for each of said power means carried by and movable with said primary platform,

(f) releasable means for positively locking said platform in a desired elevated position,

(g) and step-defining superstructure carried by said primary platform, an upper portion of said superstructure being pivotally mounted for rotation on a vertical axis and defining a secondary platform which is laterally offset from said pivot axis.

2. In a device of the class described,

(a) a mobile frame,

(b) a primary platform overlying in part said frame, and mounted and guided thereon for raising and lowering movements relative thereto,

(c) power means for imparting said raising and lowering movements to said primary platform,

(d) power means for imparting forward and rearward movements to said mobile frame,

(e) independent control means for each of said power means carried by and movable with said primary platform,

(f) releasable means for positively locking said platform in a desired elevated position,

(g) and step-defining superstructure carried by said primary platform, an upper portion of said super` structure being pivotally mounted for rotation on a vertical axis and defining a secondary platform which is laterally offset from said pivot axis,

(l1) said frame comprising an elongated generally rectangular main frame section and an extension section which projects laterally from one side of said main frame section.

3. In a device of the class described,

(a) a mobile frame,

(b) a primary platform overlying in part said frame,

and mounted and guided thereon for raising and lowering movements relative thereto,

(c) power means for imparting said raising and lowering movements to said primary platform,

(d) power means for imparting forward and rearward movements to said mobile frame,

(e) independent control means for each of said power means carried by and movable with said primary platform,

(f) releasable means for positively locking said platform in a desired elevated position,

(g) and step-defining superstructure carried by said primary platform, an upper portion of said superstructure being pivotally mounted for rotation on a Vertical axis and defining a secondary platform which is laterally offset from said pivot axis,

(h) said frame comprising an elongated generally rectangular main frame section and an extension section which projects laterally from one side of said main frame section,

(i) said frame extension section being generally triangular and being provided at its apex with a vertically adjustable Outrigger wheel.

4. In a device of the class described,

(a) a mobile frame,

(b) a primary platform overlying in part said frame,

and mounted and guided thereon for raising and lowering movements relative thereto,

(c) power means for imparting said raising and lowering movements to said primary platform,

(d power means for imparting forward and rearward movements to said mobile frame,

(e) independent control means for each of said power means carried by and movable with said primary platform,

(f) releasable means for positively locking said platform in a desired elevated position,

(g) and step-defining superstructure carried by said primary platform, an upper portion of said superstructure being pivotally mounted for rotation on a vertical axis and defining a secondary platform which is laterally offset from said pivot axis,

(h) said control means including independent control switches in a common housing, and in further combination with bracket means associated with said housing for selectively detachably securing same to said superstructure for engagement by an operator located either on said primary or secondary platforms.

5. In a device of the class described,

(a) a mobile frame,

(b) a primary platform overlying in part said frame, and mounted and guided thereon for raising and lowering movements relative thereto,

(c) power means for imparting said raising and lowering movements to said primary platform,

(d) power means for imparting forward and rearward movements to said mobile frame,

(e) independent control means for each of said primary platform,

(f) releasable means for positively locking said platform in a desired elevated position,

(g) and step-defining superstructure carried by said primary platform, an upper portion of said superstructure being pivotally mounted for rotation on a vertical axis and defining a secondary platform which is laterally offset from said pivot axis,

(h) said control means including independent control switches in a common housing, and in further combination with bracket means associated with said housing for selectively detachably securing same to said superstructure for engagement by an operator located either on said primary or secondary platforms,

() and in further combination with means for positively locking the upper portion of said superstructure in selected positions of rotation about said axis.

6. In a device of the class described,

(a) a mobile frame,

(b) a primary platform overlying in part said frame, and mounted and guided thereon for raising and lowering movements relative thereto,

(c) power means for imparting said raising and lowering movements to said primary platform,

(d) power means for imparting forward and rearward movements to said mobile frame,

(e) independent control means for each of said primary platform,

(f) releasable means for positively locking said platform in a desired elevated position,

(g) and step-deiining superstructure carried by said primary platform, an upper portion of said superstructure being pivotally mounted for rotation on a vertical axis and defining a secondary platform which is laterally offset from said pvot axis,

(h) said control means including independent control switches in a common housing, and in further combination with bracket means associated with said housing for selectively detachably securing same to said superstructure for engagement by an operator located either on said primary or secondary platforms,

(i) and in further combination with means for positively locking the upper portion of said superstructure in selected positions of rotation about said axis,

(j) each of said power means being carried by said main frame section and said primary platform overlying the greater part of the area dened by said main frame section.

References Cited in the file of this patent UNITED STATES PATENTS 426,267 Greenlow Apr. 22, 1890 1,555,103 Christian Sept. 29, 1925 1,697,478 Sandberg Ian. l, 1929 3,074,507 Pelky Jan. 22. 1963 

1. IN A DEVICE OF THE CLASS DESCRIBED, (A) A MOBILE FRAME, (B) A PRIMARY PLATFORM OVERLYING IN PART SAID FRAME, AND MOUNTED AND GUIDED THEREON FOR RAISING AND LOWERING MOVEMENTS RELATIVE THERETO, (C) POWER MEANS FOR IMPARTING SAID RAISING AND LOWERING MOVEMENTS TO SAID PRIMARY PLATFORM, (D) POWER MEANS FOR IMPARTING FORWARD AND REARWARD MOVEMENTS TO SAID MOBILE FRAME, (E) INDEPENDENT CONTROL MEANS FOR EACH OF SAID POWER MEANS CARRIED BY AND MOVABLE WITH SAID PRIMARY PLATFORM, (F) RELEASABLE MEANS FOR POSITIVELY LOCKING SAID PLATFORM IN A DESIRED ELEVATED POSITION, (G) AND STEP-DEFINING SUPERSTRUCTURE CARRIED BY SAID PRIMARY PLATFORM, AN UPPER PORTION OF SAID SUPERSTRUCTURE BEING PIVOTALLY MOUNTED FOR ROTATION ON A VERTICAL AXIS AND DEFINING A SECONDARY PLATFORM WHICH IS LATERALLY OFFSET FROM SAID PIVOT AXIS. 